How to secure Toto Drake tank - 3 inches from the wall

We just had a Toto Drake II installed to replace a one piece Kohler that we had in our first floor powder room. We love it...however, are a little concerned. The tank has some play in it (it wobbles)...what I mean by that is if you push the tank or flush it, you can see it wobble a bit. Now, as I mentioned in the title of the post, the tank is about 3 inches from the wall, so there is room to move and it does not have the wall as a form of support. What I want to know is what can/should we do about it as I do not want this to lead to a leak or any further instability that will prove to be problematic.

1. Is there something we should talk to the plumber about regarding the installation? Are there bolts that should be tightened perhaps?
2. If the answer to the above is no...what other options are there? Is there a way to support the tank with some kind of shim (probably not the best word since no one would call something three inches wide a shim...but I hope you get the idea) or other set-up?

If you still have the installation booklet, you can read Step 3 Toilet Bowl Installation (This is as appears in my Toto Drake booklet) It is possible the Drake II is arranged differently. It explains that there are 3 points of contact that will actually contact the bottom of the toilet tank when properly installed. One point is front right, one is front left, and the third is back center. The two mounting bolts should be tightened alternating from bolt to bolt to keep the tension even until the three points make contact. When this is done, the tank should be rock solid. No modern floor mounted toilet requires wall contact. In fact, if your toilet did mount that closely, removing the tank lid would be difficult. My Drake has over 2 inches clearance and it is mounted on a 12" rough-in...exactly 12". So, don't worry about the 3" you have, it's fine. I think you should check the 3 contact points and tighten the bolts more. Some advise using a piece of paper between the points on the tank and bowl and quit tightening when the paper starts to bind in the gap. Under no circumstance should you shim or improvise anything to go between the tank and bowl. It might be helpful to read the "Sticky" at the top of this forum on Drake installation.